This invention relates to circuit breakers which operate automatically in response to predetermined overload current conditions to separate the contacts of the circuit breaker, thereby opening the circuit in which the predetermined overcurrent condition exists. More specifically, the invention relates to circuit breakers of the aforementioned type having an improved magnet assembly for tripping the circuit breaker to an operated condition in response to predetermined overload currents. Still more particularly, the invention relates to circuit breakers of the aforementioned type in which the operating mechanisms have very narrow transverse dimensions to enable two circuit breaker mechanisms to be assembled as separate side-by-side units within a unitary twin unit molded insulating housing.
It is known to combine a pair of circuit breaker units within a common housing to provide a twin unit circuit breaker. However, although each unit of the resulting twin unit breaker is effectively half size of its singular counterpart, it is intended to handle and interrupt the same current capacities. In particular, the current sensing bimetal and/or magnetic structures in the twin unit breakers, although being reduced in width, are intended to be fully responsive to predetermined overload currents.